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•ASTROSAT is first multi-wavelength astronomy mission from India.
•Orbit: A 650-km, near-equatorial orbit.
• It was launched by the Indian launch vehicle PSLV from Satish Dhawan S p a c e C e n t r e , S r i h a r i k o t a o n September 28, 2015.
• The expected operating life time of the satellite will be more than five years.
ASTROSAT
•Twin 38-cm Ultraviolet Imaging Telescopes (UVIT) covering Far-UV to optical bands.
•Three units of Large Area Xenon Proportional Counters (LAXPC) covering medium energy X-rays from 3 to 80 keV with an effective area of 8000 sq.cm. at 10 keV.
•A Soft X-ray Telescope (SXT) with conical foil mirrors and X-ray CCD detector, covering the energy range 0.3-8 keV. The effective area will be about 120 sq.cm. at 1 keV.
•A Cadmium-Zinc-Telluride coded-mask imager (CZTI), covering hard X-rays from 10 to 150 keV, with about 6 deg field of view and 480 sq.cm. effective area
•A Scanning Sky Monitor (SSM) consisting of three one-dimensional position-sensitive proportional counters with coded masks. The assembly is placed on a rotating platform to scan the available sky once every six hours.
ASTROSAT
ASTROSAT : role in understanding of blazars
• Dominant emission : Leptonic or Hadronic
• One Zone vs. Multi Zone emission from Blazars
• Particle acceleration in emission zones
• Origin of orphan flares (?)
• Detection of very hard spectrum. (?)
• Detection of hard spectrum from extreme blazers
Multiwaveband SED
1010 1015 1020 1025
ν [Hz]
10-15
10-14
10-13
10-12
10-11
10-10
10-9
10-8
νFν
[erg
/cm
2 /sec
]
MOJAVE
Fermi-LAT
HAGAR/MACEMAGIC/FACT
SXT
LAXPC
CZT
UVIT
10-11
10-10
10-9
νFν
[erg
/cm
2 /sec
]
Sum of Hard and Soft componentSoft jet componentHard component from base of the jetData points from Abdo et al. 2011
Swift-BATFermi-LAT(MJD 54953-54983)
Swift-XRT :MJD : 54953-54956MJD : 54953.36
Photon Index (10-300 GeV)=1.37
VERITAS
Sum of Hard and Soft component
10-11
10-10
10-9
νFν
[erg
/cm
2 /sec
]
Fermi-LAT(MJD 55973-56003)
Sum of Hard and Soft componentPhoton Index (10-300 GeV)=0.90
1010 1015 1020 1025
ν [Hz]
10-11
10-10
10-9
νFν
[erg
/cm
2 /sec
]
Photon Index (10-300 GeV)=1.17
Fermi-LAT(MJD 55063-56093)
Sum of Hard and Soft component
10-11
10-10
10-9
νFν
[erg
/cm
2 /sec
]
Sum of Hard and Soft componentSoft jet componentHard component from base of the jetData points from Abdo et al. 2011
Swift-BATFermi-LAT(MJD 54953-54983)
Swift-XRT :MJD : 54953-54956MJD : 54953.36
Photon Index (10-300 GeV)=1.37
VERITAS
Sum of Hard and Soft component
10-11
10-10
10-9
νFν
[erg
/cm
2 /sec
]
Fermi-LAT(MJD 55973-56003)
Sum of Hard and Soft componentPhoton Index (10-300 GeV)=0.90
1010 1015 1020 1025
ν [Hz]
10-11
10-10
10-9
νFν
[erg
/cm
2 /sec
]
Photon Index (10-300 GeV)=1.17
Fermi-LAT(MJD 55063-56093)
Sum of Hard and Soft component
Multi Zone SED Model of Mrk 501
Narrow powerlaw Relativistic Maxwellian
Shukla et al. 2016, ApJ
http://fact-project.org/monitoring/
Strategy to pin down the emission mechanism
]-1
s-2
F (0
.15-
10 T
eV)
[cm
0
0.5
1
1.5
2
-910×
Crab Nebula
Time21:50 22:00 22:10 22:20 22:30 22:40 22:50
Coun
ts/m
in
05
10
15 0.2 (Chi2/NDF = 32.5/30)±Bkg Rate [counts/min] = 9.9
]-1
s-2
F (0
.15-
10 T
eV)
[cm
0
0.5
1
1.5
2
-910×
Crab Nebula
Time21:50 22:00 22:10 22:20 22:30
Coun
ts/m
in
05
10
15 0.2 (Chi2/NDF = 17.1/21)±Bkg Rate [counts/min] = 9.4
1010 1015 1020 1025
ν [Hz]
10-15
10-14
10-13
10-12
10-11
10-10
10-9
10-8
νFν
[erg
/cm
2 /sec
]
MOJAVE
Fermi-LAT
HAGAR/MACEMAGIC/FACT
SXT
LAXPC
CZT
UVIT
Search for Rapid variability by MAGIC,VERITAS and MACE
• Mrk 421
• Mrk 501 ‘
• ES1959+650